Can't Upload Articles in OJS 3.3.0.3

We installed the OJS 3.3.0.3 for our journal and it was working fine. Unfortunately now we can’t upload any article and the system displays this error message. “HTTP error”

This is the content of error log
error message tjs

Any assistance will highly be appreciated.
W. Lwiza

Application Version - e.g., OJS 3.3. 0. 3:

Additional information, such as screenshots and error log messages if applicable: